History Main / JekyllAndHyde

* ''WesternAnimation/TheFairlyOddParents'' episode "Nega-Timmy" had Timmy Turner wish that he did the opposite of what his parents told him to do. The way this wish ends up backfiring is that Mr. Turner tells his son to be good, which transforms Timmy into a fanged, top hat-wearing EnfantTerrible who attempts to use a laser to start a chain of events that will lead to the destruction of Dimmsdale. Timmy ultimately returns to normal after Mr. Turner tells Timmy to be as evil as he can be in response to Nega-Timmy swaying his dad to go along with his plan by promising that one of the results will be [[SitcomArchenemsis Dinkleburg]]'s house getting obliterated.

* ''WesternAnimation/TheFairlyOddParents'' episode "Nega-Timmy" had Timmy Turner wish that he did the opposite of what his parents told him to do. The way this wish ends up backfiring is that Mr. Turner tells his son to be good, which transforms Timmy into a fanged, top hat-wearing EnfantTerrible who attempts to use a laser to start a chain of events that will lead to the destruction of Dimmsdale. Timmy ultimately returns to normal after Mr. Turner tells Timmy to be as evil as he can be.

* The second SuperheroEpisode of ''WesternAnimation/JimmyTwoShoes'' featured a large, green monster that constantly attacked Lucius. It was eventually revealed to be Samy, who was constantly transforming thanks to one of [[MadScientist Heloise's]] potions.

** In the unreleased song "Angry Blonde" (intended for ''Music/TheMarshallMathersLP'', Slim Shady would have been represented as a rage-induced physical transformation - "''you wouldn't like me when I'm angry - the Reeboks on my feet turn to Nike, and my skin pales, hair turns blond...''"

* [=MazM=] made a virtual comic adaptation of ''Literature/TheStrangeCaseOfDrJekyllAndMrHyde,'' which is pretty faithful save for Mr. Hyde being a little more bishounen than strictly necessary. And to be fair to the artist, he is never described as ugly in the book, just creepy and deep in the UncannyValley, and those aspects of his character come across just fine.

* The [[ConceptAlbum concept]] of Music/{{Eminem}}'s {{Horrorcore}} album ''Relapse'' is that when Marshall Mathers takes drugs, he becomes Slim Shady and [[SerialKiller starts stalking and murdering people]].

* ''Manga/JojosBizarreAdventureVentoAureo'': [[spoiler:The underboss of Italy's ruthless crime organization Passione is an eccentric, rather dorky young man named Vinegar Doppio, who is the most loyal subordinate of the mafia's secretive boss, and communicates with him via "telephone", AKA talking into random objects he hallucinates as telephones.]] [[spoiler:As it turns out, he doesn't realize that he and the boss are one and the same, the latter hiding in Doppio's subconscious and only surfacing when in danger of others coming close to figuring out his true identity.]]

** ''WesternAnimation/LooneyTunes'': "Hyde and Hare" (with Bugs Bunny), "Dr. Jerkyl's Hide" (with Sylvester), and "Hyde and Go Tweet" (Sylvester and Tweety).

* ''Film/AngelHeart'' (1987) with Mickey Rourke.

* ''Jekyll and Hyde... Together Again'' had Mark Blankfield going from humble doctor to drugged-out sex-crazed swinger.

* The underrated 1970 film ''The Man Who Haunted Himself''. Rather than one character (played by Creator/RogerMoore) manifesting two personalities, there are two Roger Moore's running around, with the Hyde character gradually taking over the Jekyll character's life until he's the one assumed to be the imposter.

* Master Roshi's maid Launch from ''Manga/DragonBall'', in her usual form she's a friendly blue haired woman but whenever she sneezes she turns into a mean and violent blonde woman, she reverts back with a second sneeze and has no memory of her actions in her mean form.

* ''Series/IronFist2017'': The second season introduces Mary Walker, a slightly more realistic version of Marvel's [[Characters/DaredevilCentralRoguesGallery Typhoid Mary]] from their comics. This version is a former special forces soldier and PTSD sufferer with a raging case of Hollywood dissociative identity disorder; "Mary" is a mild-mannered, fragile woman, while the amoral "Walker" has the military skills, being an effective mercenary despite her mental issues, able to take on the wielder of the Iron Fist with some smart planning and the right weapons.

Sometimes, though, the “Hyde” is not really [[DarkIsNotEvil evil; it may just be more instinctual or capable of using violence when necessary]]... See DrPediaAndMrTrope for the {{Wiki Trope|s}} version of this. Also, a "Jekyll" persona isn't necessarily entirely "good" either — it may just be subtler or more self-controlled. After all, in the original story, Jekyll created Hyde as an outlet for his darker impulses, thus acknowledging that he ''had'' such impulses. Occasionally, the situation can be resolved (not necessarily favorably) with a SplitPersonalityTakeover, or with a SplitPersonalityMerge that reconciles both sides into a healthy whole.

The trope name comes, of course, from ''Literature/TheStrangeCaseOfDrJekyllAndMrHyde'', by Creator/RobertLouisStevenson. The dual nature of Jeckyll was actually originally a TwistEnding in the case of that story, but the book became famous and [[ItWasHisSled now it no longer surprises anyone]]. Most adaptations of the work focus on the dichotomy from the start. Other occurrences of the trope may still manage to surprise, if they’re well done.

The trope name comes, of course, from ''Literature/TheStrangeCaseOfDrJekyllAndMrHyde'', by Creator/RobertLouisStevenson. The reveal was originally a TwistEnding in the case of that story, but the book became famous and [[ItWasHisSled now it no longer surprises anyone]]. Most adaptations of the work focus on the dichotomy from the start. Other occurrences of the trope may still manage to surprise, if they’re well done.

* ''Series/IronFist2017'': The second season introduces Mary Walker, a slightly more realistic version of Marvel's ComicBook/TyphoidMary from their comics. This version is a former special forces soldier and PTSD sufferer with a raging case of Hollywood dissociative identity disorder; "Mary" is a mild-mannered, fragile woman, while the amoral "Walker" has the military skills, being an effective mercenary despite her mental issues, able to take on the wielder of the Iron Fist with some smart planning and the right weapons.

* In ''ComicBook/{{Daredevil}}'', ComicBook/TyphoidMary is the second, villainous personality of the otherwise nice and peaceful Mary Walker. She also has the downright psychotic Bloody Mary personality.

* Bergman's 'Persona'. The dynamic between Elisabet and Sister Alma; the strange scenes in which one turns the other's head towards her; the reaction of Mr Vogler to Anna.

* ''Manga/RosarioToVampire'' has Moka Akashiya, a shy, well mannered girl who is not always confident. Her true self is a thuggish brute of a vampire who can kick the snot out of anyone. [[spoiler:And by true self, we mean the personality she was born with. Her "Jekyll" half was artificially created.]]

* The ''Anime/LupinIIIRedJacket'' episode "[[Recap/LupinIIIS2E16 The Two Faces of Lupin]]" involves a man who goes around impersonating the real Lupin, stealing whatever he sets his eye on before the real one can, but also murdering in cold blood. The impersonator teams up with a former friend of Lupin turned traitorous, Dr. Normil, who manages to convince the real Lupin and his gang that the horrific acts of violence the impersonator is committing are actually the result of Lupin having "Hyde's Disease", which causes him to turn violent at the stroke of midnight.

* Master Roshi’s maid Launch from ''Anime/DragonBall'', in her usual form she’s a friendly blue haired woman but whenever she sneezes she turns into a mean and violent blonde woman, she reverts back with a second sneeze and has no memory of her actions in her mean form.